1. Field of the Invention
The present invention relates to an embroidery machine which includes a device for mounting a work support frame on a rotary ring.
2. Description of the Prior Art
A conventional embroidery machine for embroidering figures on a curved work such as a cap includes a rotary ring disposed under a sewing head. The rotary ring is movable relative to the sewing head and is rotatably driven by a drive device. A support frame for mounting the work thereon is detachably mounted on the rotary ring through a mounting device.
A prior art mounting device of a roller-holder type is shown in FIG. 7. As shown in FIG. 7, a work support frame 21 on which a cap C is mounted includes a mounting portion 21a having substantially C-shaped configuration. A rotary ring 22 includes a cylindrical support portion 22a for fitting thereon the mounting portion 21a of the work support frame 21. A plurality of rollers 22b are mounted on the rotary ring 22 through leaf springs 22c, respectively, and are biased toward the cylindrical portion 22a. The mounting portion 21a of the work support frame 21 includes a plurality of recesses 21b at positions corresponding to the rollers 22b for engagement therewith.
In a mounting operation of the work support frame 21, the work support frame 21 is moved toward the rotary ring 22 in an axial direction in such a manner that the mounting portion 21a is inserted between the rollers 22b and the cylindrical support portion 22a. Then, the rollers 22b are engaged with their corresponding recesses 21b of the mounting portion 21a through the biasing force of the leaf springs 22c, and the work support frame 21 is fixed in place relative to the rotary ring 22.
In the conventional mounting device, however, the fixing force of the work support frame 21 is derived from the force of the leaf springs 22c. Therefore, the leaf springs 22c must have strong resilient forces for supporting the work support frame 21 without rattling when the rotary ring 22 is rotated. This may cause difficulties in mounting and removing the work support frame 21 since the rollers 22b must be lifted against the biasing force of the leaf springs 22c.